In a Global System for Mobile Communications (GSM) and Long Term Evolution (LTE) networking scenario, or an LTE and Universal Mobile Telecommunications System (UMTS) networking scenario, or a GSM, LTE, and UMTS networking scenario, when access network-side service load of a radio access technology (RAT) is relatively heavy, a load transfer algorithm is usually started to adjust a service policy, so as to transfer user equipment (UE) to a co-covered network of another RAT. A connected UE is load that can be currently measured and an idle UE is potential load, and the IDLE UE may initiate a service with a relatively large amount of data in the near future. The load transfer algorithm is classified into a connected algorithm and an IDLE algorithm according to a category of transferred UE. A transfer behavior of the IDLE UE is mainly controlled by a cell broadcast message.
A process of an IDLE load transfer in the prior art is specifically as follows: a network with heavier service load changes a system message that is broadcast by the network, adjusts a reselection priority of an IDLE cell with a frequency of the network to a lower level, and adjusts a reselection priority of a detected IDLE cell that is on a co-covered network of another RAT and has lighter load to a higher level, so that more UEs reselect the network of the another RAT.
A main problem that exists in the process of the IDLE load transfer in the prior art is that: reselection priorities of networks of different RATs cannot be coordinated. Generally, during initial configuration of networks, frequency reselection priorities of networks of various RATs are consistent. When an intra-RAT network unilaterally adjusts a priority, content of broadcast messages among the networks of various RATS is not coordinated and a load transfer effect is poor. For example, when load of an LTE is too heavy, the LTE broadcasts that a UMTS frequency has a high priority, and UE reselects the UMTS. After the UE reselects the UMTS, content of a system broadcast message of the UMTS network may be that the UMTS frequency has a low priority. In this case, it is greatly possible that the UE reselects the LTE again, which causes ping-pong reselection.